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contlee
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Suppose a 70kg person is in an elevator. The acceleration of the elevator is -3m/s/s. What force would the floor exert on the person? Please show work...
Force Exerted by Floor on 70kg Person in Elevator
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To determine the force exerted by the floor on a 70kg person in an elevator accelerating downwards at -3 m/s², one must apply Newton's second law. The gravitational force acting on the person is calculated as weight (mg), which equals 686 N (70kg * 9.8 m/s²). The net force can be determined by subtracting the elevator's downward acceleration from the gravitational force, resulting in a force exerted by the floor of 556 N. Participants emphasize the importance of showing work to facilitate assistance in solving the problem. Understanding the forces at play is crucial for arriving at the correct answer.
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19.
For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Figure 1 Overall Structure Diagram
Figure 2: Top view of the piston when it is cylindrical
A circular opening is created at a height of 5 meters above the water surface. Inside this opening is a sleeve-type piston with a cross-sectional area of 1 square meter. The piston is pulled to the right at a constant speed. The pulling force is（Figure 2）： F = ρshg = 1000 × 1 × 5 × 10 = 50,000 N.
Figure 3: Modifying the structure to incorporate a fixed internal piston
When I modify the piston...
Let's declare that for the cylinder,
mass = M = 10 kg
Radius = R = 4 m
For the wall and the floor,
Friction coeff = ##\mu## = 0.5
For the hanging mass,
mass = m = 11 kg
First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on.
Force on the hanging mass
$$mg - T = ma$$
Force(Cylinder) on y
$$N_f + f_w - Mg = 0$$
Force(Cylinder) on x
$$T + f_f - N_w = Ma$$
There's also...
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